<template>
  <Select 
    v-bind="$attrs" 
    :open="isOpenOptions && ((Array.isArray(state) && state.length > 0) || (!Array.isArray(state) && state !== ''))" 
    @change="handleChange" 
    @select="handleSelect"
    @focus="handleFocus"
    @blur="handleBlur" 
    @mouseenter="handleMouseenter"
    @mouseleave="handleMouseleave"
    @mousedown="handleMousedown"
    @search="handleSearch"
    :filterOption="false"
    >
    <!-- :options="customOptions ? undefined : getOptions" -->
    <template #[item]="data" v-for="item in Object.keys($slots)">
      <slot v-if="item !== 'customOptions'" :name="item" v-bind="data || {}"></slot>
    </template>
    <slot name="customOptions" v-bind="getOptions || []"></slot>
    
    <template #suffixIcon v-if="loading">
      <LoadingOutlined spin />
    </template>
    <template #notFoundContent v-if="loading">
      <span>
        <LoadingOutlined spin class="mr-1" />
        {{ t('component.form.apiSelectNotFound') }}
      </span>
    </template>
  </Select>
</template>
<script lang="ts">
  import { defineComponent, PropType, onUnmounted, ref, watchEffect, onMounted, computed, unref, watch } from 'vue';
  import { Select } from 'ant-design-vue';
  import { isFunction } from '/@/utils/is';
  import { useRuleFormItem } from '/@/hooks/component/useFormItem';
  import { useAttrs } from '/@/hooks/core/useAttrs';
  import { get, omit } from 'lodash-es';
  import { LoadingOutlined } from '@ant-design/icons-vue';
  import { useI18n } from '/@/hooks/web/useI18n';
  import { propTypes } from '/@/utils/propTypes';
  // 防抖动
  import { debounce } from 'lodash';

  type OptionsItem = { label: string; value: string; disabled?: boolean };

  export default defineComponent({
    name: 'ApiSelect',
    components: {
      Select,
      LoadingOutlined,
    },
    inheritAttrs: false,
    props: {
      value: [Array, Object, String, Number],
      numberToString: propTypes.bool,
      api: {
        type: Function as PropType<(arg?: Recordable) => Promise<OptionsItem[]>>,
        default: null,
      },
      // api params
      params: {
        type: Object as PropType<Recordable>,
        default: () => ({}),
      },
      // support xxx.xxx.xx
      resultField: propTypes.string.def(''),
      labelField: propTypes.string.def('label'),
      valueField: propTypes.string.def('value'),
      immediate: propTypes.bool.def(false),
      customOptions: propTypes.bool.def(false),
    },
    emits: ['options-change', 'change', 'update:value', 'select'],
    setup(props, { emit }) {
      const options = ref<OptionsItem[]>([]);
      const loading = ref(false);
      const preParam = ref();
      const emitData = ref<any[]>([]);
      const attrs = useAttrs();
      const { t } = useI18n();
      const isChange = ref(false)
      const searchValue = ref<any>()
      const isOpenOptions = ref<boolean>(true)
      const isMouseenter = ref<boolean>(false)

      // Embedded in the form, just use the hook binding to perform form verification
      const [state, setState] = useRuleFormItem(props, 'value', 'change', emitData);

      const getOptions = computed(() => {
        const { labelField, valueField, numberToString } = props;
        return unref(options).reduce((prev, next: Recordable) => {
          if (next) {
            const value = next[valueField];
            prev.push({
              ...omit(next, [labelField, valueField]),
              label: next[labelField],
              value: numberToString ? `${value}` : value,
            });
          }
          return prev;
        }, [] as OptionsItem[]);
      });

      watchEffect(() => {
        props.immediate && fetch();
      });

      watch(
        () => props.params,
        () => {
          if (JSON.stringify(preParam.value) === JSON.stringify(props.params)) {
            return
          }
          fetch();
          preParam.value = props.params
        },
        { deep: true }
      );

      async function fetch() {
        const api = props.api;
        if (!api || !isFunction(api)) return;
        options.value = [];
        try {
          loading.value = true;
          const res = await api(props.params);
          if (Array.isArray(res)) {
            options.value = res;
            emitChange();
            return;
          }
          if (props.resultField) {
            options.value = get(res, props.resultField) || [];
          }
          emitChange();
        } catch (error) {
          console.warn(error);
        } finally {
          loading.value = false;
          //判断选择模式，multiple多选情况下的value值空的情况下需要设置为数组
          unref(attrs).mode == 'multiple' && !Array.isArray(unref(state)) && setState([]);
        }
      }

      async function handleFetch() {
        await fetch();
      }
      
      function emitChange() {
        emit('options-change', unref(getOptions));
      }

      function handleChange(_, ...args) {
        emitData.value = args;
      }

      const handleFocus = () => {
        isOpenOptions.value = true
      }
      const handleMouseenter = () => {
        isMouseenter.value = true
      }
      const handleMousedown = () => {
        isOpenOptions.value = isMouseenter.value
      }

      const handleMouseleave = () => {
        isMouseenter.value = false
        isOpenOptions.value = isChange.value ? isOpenOptions.value : true
      }

      const handleBlur = (value) => {
        if (state.value === '' || !options.value || options.value.length === 0) {
          isOpenOptions.value = false
        }
         console.log('handleBlur: ', value);
      }
      const doSearch = async (keyword, option) => {
        isChange.value = false
        console.log('keyword', state.value);
        await handleFetch()
      }
      const handleSelect = (value) => {
        isChange.value = true
        setState( (value != null && value != '') ? value : undefined)
        console.log('handleSelect: ', state.value);
        isOpenOptions.value = false
        emit('select', unref(state));
      }
      const handDebounceSearch = debounce(doSearch, 1000);  //防抖1s

      const handleSearch = (value, options) => {
        try {
          setState(value || '')
          emit('update:value', unref(state));
          if (state.value === '') {
            isOpenOptions.value = false
            return
          }
          isOpenOptions.value = true
          loading.value = true;
          handDebounceSearch(value, options)
        } catch(e) {
          loading.value = false;
          console.log('error', e);
        } finally {
        }
      } 

      const reset = () => {
        setState('')
      }

      onUnmounted(()=>{
        handDebounceSearch.cancel()
      }) 

      return { 
        state, attrs, getOptions, loading, t, isChange, searchValue, isOpenOptions,
        handleFetch, handleChange, fetch, handleMousedown, handleFocus, handleMouseenter, handleMouseleave,
        handleBlur, handleSearch, handleSelect, reset
      };
    },
  });
</script>
